Process for the production of acetylene by incomplete combustion of hydrocarbons



Aug. 16, 1955 H. SACHSSE ETAL PROCESS FOR THE PRODUCTION OF ACETYLENE BY INCOMPLETE COMBUSTION 0F HYDROCARBONS Filed May 18, 1950 FIG! INVENTORS. HANS SACHSSE THOMAS KOSBAHN ERWIN LEHRER 2,715,648 Patented Aug. 16, 1955 PROCESS FOR THE PRODUCTION OF ACETYLENE gY INggMPLETE COlVlBUSTION OF HYDRO- ARBO Hans Sachsse, Kelheim (Danube), Thomas Kosbahn,

Heidelberg-Rohrbach, and Erwin Lehrer, Bad Duerkheim, Germany, assignors to Badische Anilin- & Soda- Fabrik Aktiengesellschaft, Ludwigshafen (Rhine), State of Rheinland-Pfalz, Federal Republic of Germany Application May 18, 1950, Serial No. 162,687 In Germany October 1, 1948 Public Law 619, August 23, 1954 Patent expires October 1, 1968 3 Claims. (Cl. 260679) The present invention relates to the production of acetylene by incomplete combustion of hydrocarbons. The object of this invention is to provide an improved apparatus for this process.

According to a prior art method for the large-scale production of acetylene by the incomplete combustion of hydrocarbons and oxygen with the formation of a flame, a stable burning flame can be maintained and good yields of acetylene be obtained, by causing the flame to form in a substantially free reaction chamber which has its greater extension perpendicularly to the direction of flow of the gases and of which the extension in the direction of flow of the gases is at the most about 200 millimetres. The mixture of hydrocarbons and oxygen is led into the reaction chamber preferably through a gas distributor which consists of a plurality of parallel tubes or channels for the passage of the gas mixture and which serves to distribute even large amounts of gas uniformly over the flat reaction chamber. The maximum permissible internal width of the tubes or channels was situated in the neighborhood of about millimetres, but in practice 10 millimetres were not exceeded, as with larger gas outlet openings a good ignition of the gas mixture and a firm adherence of the flame to the reaction chamber, in particular an avoidance of the striking back of the flame, as Well as a rapid and complete conversion of the gas stream over the short distance did no longer seem to be ensured.

We have now found that appreciably wider gas outlet openings, for example even internal widths of up to about millimetres, can be employed if the tubes or channels are so constructed, for example by providing them with internal guide devices, that a spiral movement is imparted to the gas streams. The lengthening of the flame cone which occurs as a result of the larger diameter of the tubes or channels is counteracted by the spiral movement, so that the requirement for the shortest possible flaming space of not more than about 200 millimetres is met as before.

The novel constructional arrangement according to the invention gives gas distributors a considerably longer life, especially when they are made in the form of blocks of ceramic material perforated by parallel channels.

The invention is illustrated in the accompanying drawings in which Figure 1 shows in plan and sectional elevation a known type of gas distributor and Figure 2 shows in plan and sectional elevation a gas distributor according to the invention.

The blocks a in Figure 1, being exposed to the flame burning in the reaction chamber b underneath, have to pass rigorous thermal tests and as a result have to be replaced quite frequently. The blocks according to this invention (Figure 2), however, which are fitted with Wider and hence fewer channels and which are provided with means imparting a spiral movement to the gases passed therethrough, are considerably more lasting than the blocks hitherto employed. a

The following example will further illustrate this invention but the invention is not restricted to this example.

Example A mixture of about per cent of methane and 35 per cent of oxygen is introduced at a temperature of 600 C. through the gas distributor a into the reaction chamber 15. For the purpose of igniting the gas mixture, methane is first led in Without admixture of oxygen, and small pilot flames are ignited in the reaction chamber. Then the mixture of methane and oxygen is allowed to flow in instead of the methane alone which sets the flame going. Into the gas leaving the reaction chamber water is sprayed by means of nozzles in order to quench it. The amount of water used is about 5 to 20 litres per cubic metre of methane being worked up. From 1000 cubic metres of the mixture of methane and oxygen there are obtained 1200 cubic metres of a gas mixture containing 8 per cent of acetylene, 4 per cent of carbon dioxide, 26 per cent of carbon monoxide, 57 per cent of hydrogen and 5 per cent of methane.

When using a gas distributing block as shown in Figure 1 with 36 channels of 10 millimetres diameter each, the average life of a block under the said conditions is about 6 weeks. The block, besides having to stand rigorous heat conditions, is also subject to the wear residing in that coke deposits are formed on the gas outlet side thereof where they must frequently be removed mechanically. Gas distributing blocks as shown in Figure 2 with 9 channels each having a width of 20 millimetres have an average life of 4 months.

What we claim is:

l. A process for the production of acetylene by the incomplete combustion of hydrocarbons with oxygen in a flame reaction after the gases have been mixed which comprises passing said hydrocarbons and oxygen into a reaction zone through a block of ceramic material provided with channels'having parallel side walls, the width of each of said channels being in excess of 10 millimetres and not exceeding 35 millimetres, and imparting a spiral movement to the gas streams passing through said channels.

2. A method of producing acetylene by the incomplete combustion of methane with oxygen in a flame reaction after the gases have been mixed which comprises igniting methane in a reaction zone, passing a mixture of methane and oxygen into said reaction zone through a plurality of parallel channels in a block of ceramic material, the width of each channel being in excess of 10 millimetres and not exceeding 35 millimetres, and imparting a spiral movement to the gas streams passing through said channels.

3. A process for the production of acetylene by the incomplete combustion of hydrocarbons with oxygen in a flame reaction which comprises passing a gaseous mixture of said hydrocarbons and oxygen through a block of ceramic material provided with channels having parallel side walls, the width of each of said channels being in excess of 10 millimetres and not exceeding 35 millimetres, imparting a spiral movement to each of the streams of said mixture in said channels while passing therethrough, discharging said streams of said mixture from said block into one end of a reaction zone substantially uniformly over the end, and incompletely burning said mixture in said reaction zone.

References Cited in the tile of this patent UNITED STATES PATENTS 1,322,249 Leland Nov. 18, 1919 (Other references on following page) 3 V UNITED STATES PATENTS Colman June 14; 1932 Krejci May 29, 1945 Stadler June; 13; 1950 Krejci Nov. 4, 1952 FOREIGN PATENTS 7 Germany May'21, 193 0 7 Germany Mar. 25, 1935 Germany Nov. 5, 1953 

1. A PROCESS FOR THE PRODUCTION OF ACETYLENE BY THE IMCOMPLETE COMBUSTION OF HYDROCARBONS WITH OXYGEN IN A FLAME REACTION AFTER THE GASES HAVE BEEN MIXED WHICH COMPRISES PASSING SAID HYDROCARBONS AND OXYGEN INTO A REACTION ZONE THROUGH A BLOCK OF CERAMIC MATERIAL PROVIDED WITH CHANNELS HAVING PARALLEL SIDE WALLS, THE WIDTH OF EACH OF SAID CHANNELS BEING IN EXCESS OF 10 MILLIMETRES AND NOT EXCEEDING 35 MILLIMETRES, AND IMPARTING A SPIRAL MOVEMENT TO THE GAS STREAMS PASSING THROUGH SAID CHANNELS. 